1. Technical Field of the Invention
The present invention generally relates to a blower module mounted upstream of either a heat exchanger or air filter in an automotive ventilation system.
2. Description of the Prior Art
In most center mounted air-handling systems the blower scrolls have a constant depth extending circumferentially from a cut-off edge to the exit. These types of blower units are typically formed as an upper part and a lower part. The motor and the fan or fans are inserted in the lower part, and then covered by the upper part. Air enters the scroll chamber through an air inlet. As the air rushes axially toward the back of the fan and the scroll chamber, opposite the air inlet, a high pressure zone is created near the bottom of the scroll chamber, distal from the air inlet, and lower pressure-zone near the top of the scroll chamber, adjacent the air inlet. This pressure differential results in air circulation inside the scroll chamber between the high pressure zone and the low pressure zone, which reduces the efficiency and blower capacity of the system.
Further, the recent designs of these types of blower assemblies may include a secondary ring extending around the air inlet to reduce the amount of high pressure air leakage from the scroll chamber, back through the air inlet. Typically, these secondary rings have a diameter greater than the fan outer diameter and leveled axially with the fan ring that leaves minimal or no axial clearance between the top of the fan and the ring to allow the fan to be removed laterally from any side without completely dis-assembling the blower assembly.
Therefore, there is a need for a dual fan, single motor blower assembly which will reduce the amount of axial circulation of the air within the two scroll chambers for the two fans and thereby increase the efficiency and blower capacity of the blower assembly. Further, there is a need for a blower assembly that has a secondary ring and allows the fan or fans to be removed laterally from a side without completely dis-assembling the blower assembly.
A principle object of the present invention is to provide a dual fan, single motor blower assembly which will provide a reduced pressure differential between the air located near the bottom of the scroll chamber and the air located adjacent the air inlet, thus reducing the amount of axial air circulation within the scroll chamber and thereby increasing the efficiency and blower capacity of the blower assembly.
It is also an object of the present invention to provide a blower assembly that reduces the amount of air leakage from the scroll chamber between the fan and scroll inlet side to the air inlet and allows the fan or fans to be removed laterally from a side without completely dis-assembling the blower assembly.